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I found this question looking for alternatives to backtick as it started to cause trouble after I got used to using backticks instead of $() in shells. Also it becomes a pain once you start writing a lot of Markdown. I've been using it for several years, but unfortunately I'll have to change it now.
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kirelaginJul 1 '14 at 20:09

In .tmux.conf I also have bind-key C-a set-option -g prefix C-a. Whenever I need to use backticks I hit `-Ctrl-a which sets my prefix to C-a. And I have bind-key C-b set-option -g prefix ` so I can hit C-a-C-b to go back
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borisDec 24 '14 at 23:14

What if you're writing markdown? How do you escape the prefix?
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Ollie FordJul 12 at 23:29

Ctrl+A is also known to cause problems with Emacs, including Bash in Emacs mode. It sounds like this is not a problem for you.

Ctrl+O is the other option I've seen. Apparantly, this is the default in RatPoison (this is an X window manager that doesn't need a mouse). I've used Ctrl+O when using nested screens: Ctrl+O for the outer one and Ctrl+A for the inner ones. Worked well, but kinda scared my colleagues. :-)

I was just thinking and if you use vi rather than Emacs, there are a few alternatives. Ctrl+G isn't used by much, for instance.

I agree with @MuQiao. Ctrl-o is used in Vim to jump to an older cursor position (equivalent of back button in many IDEs), a feature I use very often while browsing code in Vim. Ctrl-b is synonymous to PageUp in Vim. I don't use Ctrl-b at all on Vim. So for Vim users like me, Ctrl-b is still a better choice than Ctrl-o. I use C-j as my prefix key since C-j is synonymous to j or <Down> in Vim and nobody uses C-j to move one line down in Vim. I have this in my ~/.tmux.conf: set -g prefix2 C-j; bind-key C-j send-prefix -2
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Susam PalApr 10 '14 at 9:44

I use a complex system for screen. My default escape is set to \140\140, which is backtick. The Ctrl-A complicates both Emacs and command line editting for me within Zsh, and I dislike Ctrl-O (2 hand operations for most screen actions).

I rebind 's' to screen 1 so that new sessions are created from left to right on the keyboard starting at 1. This allows me to reserve screen 0 for what I consider persistent or reference windows. It's very quick one handed gesture to (backtick)1, (backtick)2, (backtick)3 to swap between windows.

The issue with using backtick in a unix environment is when attempting to cut and paste shell/perl script code. For this reason I bindkey F11/F12 to switch between my escape character.

Is there a way to set some kind of minimal timeout for prefix+other_key combo in tmux so when pasting code it doesn't trigger any command but when typing backtick+key from keyboard it does because the pause between backtick and the other key was longer?
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sickillMay 5 '12 at 16:15

I use Ctrl-Q in tmux and it has worked well so far. I have to mention, though, that it conflicts with shell flow control. By default, Ctrl-Q is used to re-enable output after stopping it with Ctrl-S. Having been surprised by a stuck shell a few times after accidentally hitting Ctrl-S, I have learned not to press Ctrl-S.

(One could also turn off flow control altogether with stty -ixon, or bind different keys to stty start and stty stop.)

Still close to ctrl-a (in fact, for most typers it will use the same two fingers they used for ctrl-a), so the muscle memory switch from ctrl-a to ctrl-s is trivial -- for me, it became second nature within about an hour of first trying it.

Frees up ctrl-a for emacs-style "back to beginning of line" or vim-style "increment number" operations. Or hey, for running screen inside a tmux pane without needing to worry about escaping prefix characters to control the embedded screen instance. (I often do this using a local tmux with panes containing ssh sessions to remote servers, in which I run screen)

Doesn't override or add escaping-requirements to any other commonly-used terminal functionality. nothing the vast majority of people use today is on ctrl-s!

Of course, the reason that nothing is on ctrl-s is that in the terminal, it traditionally is used for flow control, dating back to the days before paging tools like more and less were common. I'm sure some GUI terminal program somewhere still has that flow-control functionality enabled by default, but I haven't actually bumped into one; the gui terminal programs I've tried all seem to completely ignore it by default, which makes that convenient key combination available for more productive uses.

So if you're not actually using screen/tmux from within (for example) a raw Linux terminal, but rather from a GUI-based terminal, then I recommend giving ctrl-s a try; it's made zipping about in tmux and screen a lot more convenient for me.

Personally, b is just too far away from Ctrl for me. When I use tmux, I alway change the binding from C-b to C-a. The main conflict with C-a is select all, but I have not found this to be a problem with the programs I use tmux with.

I use this as well. C-Space is quite easy to type.
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kzhAug 21 '14 at 16:56

The backtick is pretty good. However its not terminal friendly as it turns out. You definitely cannot go wrong with xterm on linux, but terminals like putty and iTerm2 (macos) have issues emulating it properly. Luckily in iTerm2 you can workaround it in the configuration. I don't use windows/putty a lot, so ctrl-space seems to be a feasible workaround. :)
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AlexAug 23 '14 at 19:02